Power transmission mechanism



March 14, 1933. P; M. 'SALERNl 1,901,194

POWER TRANSMISSION MECHANISM Filed Oct. 8, 1930 12 Sheets-Sheet 1 W a 5/9 19 /6 155 106 2/ 2a 17 12 20" March 14, 1933, r P. M. SALERNI1,901,194

I POWER TRANSMISSION MECHANISM I Filed Oct. 8; 1930 12 Sheets-Sheet 2POWER TRANSMISS ION MECHANISM Filed Oct. 8, 1950 12'Sheeis-Sheet 3 \gaJ6 Ma rch14,1933. RMQSALE RNI r 1,901,194

POWER TRANSMISSION MECHANISM Filed Oct. 8, 1930 12 Sheets-Sheet 4 r1933. P. M. SALERNI 1,901,194

POWER TRANSMISSION MECHANISM Filed -Oct. 8, 1930 l2 Sheets-Sheet 5 IMarch 14, 1933. MSSALERN, 1,901,194 I POWER TRANSMISSION MECHANISM FiledOct/8, 1930 12 Sheets-Sheet 6 March 14, 1933. P, M. SALERNI 1,901,194

POWER TRANSMISSION MECHANISM Filed 0101;. 8; 1930 12 Sheets-Sheet 7March 14, 1933. P. M. SALERNI 1,901,194

POWER TRANSMISSION MECHANISM Filed 001;. 8, 1930 12 Sheets-Sheet 9 March14, 1933. P. M. SALERNL 1,901,194

. POWER TRANSMISSION MECHANISM Filed Oct 8, 1930 12 Sheets-Sheet 1oMarch 14, 1933. VP. M. SALVERNI 1,901,

POWER TRANSMISSION MECHANISM Filed 001:. 8. 1930 12 Sheets-Sheet l l Wi1'; ll 25 March 14, 1933 P. M. SALERNI 1,901,

POWER TRANSMISSION MECHANISM Filed Oct. 8, 1930 12 Sheets-Sheet 12Patent ed Mar. 14, 1933 uuirao STATES: OFFICE rrano nanmno suinam, orwasmrn sraalmnnon, imam rowan rRANsmrssio-rr 'mnc'nnmsu Applicationfiled October 8, 1980, Serial No. 48?,188, and in Great Britain October16,

This invention relates to epicyclic or differential change speedgearing, particularly but not exclusively for use-in connection with thepower transmission mechanism of mechania cally propelled vehicles. Theobject of the invention is to provide gearing of this"kind whichcomprises a number of novel and important features and. possesses manyadvantages over the usual type of epicyclic gearing.

For instance, the gearing according to this invention is compactlyarranged in a small space and the engagement of the different members ofthe gearing is considerably simplified whilst instead of'usingfrictional gripping or locking mechanism such as is genera ly employedin existing epicyclic gearing, ineans are used that provide under allconditions a ositive bi-directional drive through material under shearload. A further advantage is that the engagement of the differentmembers of the gearing can be easily effected without undue, shock bythe mere displacement of a single operating or selecting lever withoutnecessarily disconnecting the engine from the transmission mechanism,the drive being always re-established in or by the gearing at the exactmoment at which the engine, the change speed gear and the road wheelsare rotating at their correct relative speeds.

The epicyclic or differential gearing to which the present inventionrelates, c0mprises a drivin sun member or gear wheel, one or more rivensun members or gear wheels, a planet carrying member with one or morecompound planet pinions thereon and an internally toothed annular memberaround and engaged. by certain of the planet pinions and according tothe present invention I provide axially movable clutch means rotatablewith the driven shaft and capable of being moved within, into or throughthe driven sun member (or members) so as to engage with the drivingshaft or the driving sun member or a part connected therewith. The saidclutch means may engagewith the driving member or the driven member, orwith both of them simultaneously and separate clutchmeans maybe providedfor engaging with the other members of the gearing. It is, however,

preferred to provide a single set of 'dogs,

teeth or the like for engaging with dogs teeth or the like on thediiferentmembers of the gearing. In order to enable the clutch means or.dogs that connect the different members of the gearing with the drivenshaft to be moved within, into or through the driven'sun member ormembers), this member may be in the form of an externally su portedannulus in or through which t e clutch means can be axially or slidablymoved, 0 and it may be provided with internally disposed dogs which can.be engaged by axially movable dogs .that connect the driven sun memberwith the driven shaft, which dogs. 4 may also engage with the-dogson'the driving 6 sun member, although separate dogs may be provided forengaging with the-said latter member. The'dogs or the like that areprovided on the various members of the gearing are preferably internallydisposed around the driven shaft within the limits of the endbearings ofthe assembled members, inacentral space actually within the bearing,.inwhich space the clutch means comprising the axially movable dogs can beslidably moved to effect the desired engagement for rotatably connectingany of the said members with the. driven shaft, this engagement takingplace actually within the said members of the gearing and not externallyas is the case when a number of concentric sleeves are provided on 1 thedifferent members of the gearing, which sleeves carry engaging dogs ontheir extremities or on their externally projecting parts. In thepresent invention the axially movable sleeve carrying the dogs forengaging the dogs on the members of the gearing, extends outwardlybeyond the gearing where it is provided with operating means thatslidably movethe sleeve to connect the various toothed members with thedriven shaft actually within the earing. The eature of providing amovable clutch member that canengage with any one of the other membersor with all of only the driving and /or driven members, simplifies theconstruction and avoids the necessity for several of such clutch membersand several concentric sleeves carrying clutch teeth. In referring tothe driving sun them, or with I member in this specification and in theclaiins driven sun member (or members) is made of annular formation sothat it can be supported internally to enable the aforesaid clutchmember to be moved into and through the same for engaging purposes, thisfeature also simplifyin the construction in that internal bearings orthe driven sun member (or members) can be dispensed with, externalsupporting means being substituted therefor. A further feature of theinvention is the rovision in earing such as that aforesai of gear whee sor toothed members of which. the teeth are of helical formation, suchgear wheels having the advantage that they are silent in operation.Although any. form of thrust bearing may be used in conjunction with'thehelical gear wheels, I provide imroved bearings as hereinafterdescribed; Another feature is the provision of improved means forsupporting t e various parts of the gearing in such manner as to avoidthe use of bronze b'ushes and special lubricatingmeans such as areusually employed, and in' or co-acting this respect inter-supportinrollers, circular bearing sur aces, tracks or the like are providedwhereby any one or more of the gear wheels 'or toothed members can beroperly supported or positioned. These rol ers, bearing surfaces or-thelike maybe so arranged as to ensure proper meshing of the teeth of thevarious gear wheels I, or toothed members. These rollers etc., arepreferably such'that they are co axial with the gear wheels or memberswith which they are associated, and preferably the diameters of theserollers or bearing surfaces are eq'ual to the pitch circle diameters ofthe gear wheels or members with which they are co-axially aligned. Forexample, the driving sun wheel has associated therewith a roller supportaround which travel rollers associated with the larger planet pinionsthat are in mesh with the driving sun wheel, these lanet'" rollers alsoengaging with and travelling on an internal roller track in theinternally toothed member or annulus, the said roller supports, theplanet rollers and the annulus roller track having diameters which arerespectively equal to the pitch circle diameters of the driving sunwheel the planet pinions in mesh therewith and t e internal annulusteeth engaged by the said planet pinions. The aforesaid driven sun wheelis externally supported by inter-engaging and co-acti'ng rollers orcircular bearing surfaces, for which purpose one or more rollers of adiameter e ual to the pitch circle diameter of the teeth 0 this sunwheel are associated with the latter and are supported by externalrollers or bearing surfaces associated with the smallerplanet pinionsengaging with the driven sun wheel, these smaller planet rollers orbearing surfaces bein of a diameter equal tothe pitch circle diameter ofthe smaller planet pinions. Not only does the arrangement of on theannulus. According to a further fea ture improved thrust bearings areprovided to take the axial thrust due to the helical gear wheells andtoprevent axial displacement or misa 1 ment of the partsythese bearingsinter-engaging and co-acting rollers and the like ensure proper meshingof the teeth of-the beingm the form of inter-enga 'ng flanges or sidecircular bearing surfaces ocated at or about the itch circle diametersof the ear K wheels wit which they are associated. he saidflan es orcircular bearing surfaces may 'be associated with the pitch circlerollers, tracks or the like hereinbefore referred to, so that thelatterform combined journal bearings and thrust bearings.- Another feature isthe provision of means whereby the gearing alwa s transmits the power ina positive manner, i-directionally, through material under shear load,so that the use of frictional or ratchet means for holding certain ofthe members against rotation can be-avoided. A further feature is theprovision of improved means for looking or gripping the internallytoothed member or annulus, and the planet carrier or cage, so thateither can be held against rotation as re uired for certain gears orspeeds, the said loc ing or gripping means being adapted to engage withand to grip either of the members referreddto at or about the time whenits rotation tends to cease, ceases or begins to be reversed. Althoughthe construction of lockin means for holding the said annulus or the panet carrier is preferably such as to permit of a positive bi-direc-*tional drive through material under shear load when either member islocked, the feature of locking at or about the moment when the rotatingmember ceases to rotate or begins to rotate in the reverse direction,may be applied to aconstruction in which the said rotating member isheld by frictional or other glil'ip ing means, thus overcomingdifliculties t atsuch frictional gripping means or the like. For thepurpose of preventing engagement of the lockingv or grlpping means withthe rotating member until such time as the rotation of the latter ceasesand tends to reverse,

ave been experienced in connection with balking means are provided, andsuch means such manner that when the latter ceases to rotate or torotate in the reverse direc-- tion, it dis aces the balking ring whichthen allows the ocking means to. en

age with and rip the said member. A furt er feature is t e provision ofinternal balking or synchrothe rotatingmember with which the said clutchmember or when the speed of I approximately equal to that of the drivenmember, thus permitting the en agement of the required parts tore-connect e transmission and re-establish the drive. A further featureis the provision of improved operatsleeve is to be connected,

ing mechanism which comprises a single lever that can be displaced inone direction for slidably moving the clutch member or sleeve thatconnects the driven member to the required gear wheel or rotating memberof the gearing and can also be moved in another direction forthe purposeof operating the locking means that engage with either the annulus orthe planet carrier or. cage. The said lever may be movable within a gatehaving a medial slot that enables the lever to be moved in the directionof the axis of the gear for operating the slidable clutch member orsleeve, medial slot into which the lever can be moved on one side foroperating the locking means associated with the annulus and on the otherside for operating the locking means associated with the planet carrieror cage.

In order that the clearly understood and readily carried into effect,the same will now be described more fully with reference to theaccompanying drawings in which a Figure 1 is avertical longitudinalsectional view of one construction of the difi'erential or epicyclicgearing embodying this invention.

Figure 2 is an end view looking in the direction of the arrow X inFigure 1.

Figure 3 is a vertical sectional view showing more particularly thecontrolling or operating mechanism for actuating the gearing, theoutline of the latter being represented in dotted lines in this figure.

Figure 4 is an end view of the controlling or operating mechanismlooking in the direc tion of the arrow Y in Figure 3.

parts attain rotational synchronism.

the former is equal to or and lateral slots on each side of the saidinvention may be Figure 4a is an enlar ed sectional view of part'of themechanism s own in Fi ure 4.

Figure 5 is a plan view partly in section of part of the controlling oroperating mech anism. 7,

Figures 6 and 7 are transverse sectional views taken on thelines VI-VIand VII- VII',.of Figure 1. v

Figures 8 to llare detail views (looking in the direction of the arrow Zin Figure 3) of parts of the controlling or operating mechanlsm shown indifferent positions.

Figure 12 is a detail view hereinafter referred to.

Figures 13 to 20 are diagrams illustrating the gearing (mainly in dottedlines) and the controllin oroperating lever in different positions inits gate.

Figures 21 to 28 are diagrammatic views 7 of t e internal synchronizingor bulking mechanism. Figure 29 is an end view similar to Figure 4illustrating'a modification hereinafter referred to.

The gearing is contained in a casing 1 in which at one end the drivingshaft 2 is suported in a ball bearing, the driven shaft 3 ing supportedin a ball hearing at the other end of the casing 1. The inner or freeend of the driven shaft 3 is formed with a spigot that fits within theinner end of the driving shaft 2 as shown in Figure 1. The drivingshaft.2 is formed with or has secured thereon a driving sun gear wheel 4which is in -mesh with the larger planet pinions 5 of preferably threecompound planet pinions (see Figures 2, 6 and 7) of which the smallerpinions 6 are in mesh with a driven sun gear wheel 7 of annular orhollow formation as shown. The compound planet pinions 5, 6,

are supported at their ends in ball bearings 50 and 6a mounted in endplates 8 and 9 that form part of a cage or carrier, the body 10 of whichis illustrated in perspective in Figure 12 the said end plates 8 and 9in the exam le shown being secured tothe cage body 10 8y means of bolts11 that extend through substantial bosses on the cage body and aresecured in position b the end plates secure whole forming the nutsso asto clamp y to the body 10, the planet cage or carrier which willhereinafter be referred to as the cage 10. The body and the end platesare preferably made of duralumin. Surrounding the said cage 10 is anannulus 12 which at the rear end is formed or provided with a plate 13,whose inner part is mounted in a ball bearing 14 supported in adiaphragm or web la-forming part of the casing 1 the said annulus 12being provided with internal teeth 15 with which mesh the larger planetpinions 5 of the three compound planet pinions. P 7

In the example illustratedthe teeth of the different gear wheels andpinions are of helical formation. At or near the ends of of the compoundplanet pinions are. provided 2 rollers or c rcular bearing surfaces16and 17 the diameters of which are equal to the diameters of the pitchcircles of the larger,

planet pinions5, the three rollers 16Abe1ng adapted to travel around aroller support or circular bearing surface 18 which is provided aroundthe drivingshaft 2 and is-of a diameter equal to the diameter of thepitch circle of the driving sun wheel 4. The said rollers 16 and 17 alsocontact'with and travel around roller tracks or bearings 19 and 20respectively, provided on the internal surface of the aforesaid annulus12 the diameters of the said roller tracks 19 and 20 being equal to thediameter of the pitch circle of the internal teeth of the annulus. Thesaid rollers 17 are each provided with a reduced smaller planet pinion6.

circular portion 21 constituting another roller or bearing surface andhaving a diameter equal to the diameter of the itch circle of the achcompound planet is also provided with another roller or circular bearingsurface 22 having a diameter equal to that of the reducednoller portion21 of the roller 17. The driven sun wheel 7 is provided at its sideswith rollers or circular bearing surfaces 23 and 24 which are each of adiameter equal to the pitch circleof its teeth and which engage respec:

' tivelywith the rollers or bearing surfaces 21 and 22 on the threecompound lanet pinions so that the driven sun wheel (which is of annularformation. as aforesaid) is supported within and by the said rollers orsup orts 2-1 and 22 on the equi-spaced compoun planet pinions. Therollers or bearing surfaces 23 and 24 particularly the former are madeseparate from the driveh sun wheel 7 and the compound roller-support 17and 21 is made separate from the compound planet pinion as shown inFigure 1, in order to facilitate assembly of the parts. The compoundroller support 17 and 21 is held against endwise displacement on thecompound planet by a spring ring 21a. The internal gearin and associatedparts after assembly are nally held in position by the end cage plaw 9which is bolted to the cage 10 and the other cage plate 8 by the bolts11. The various through it to connect or engage different parts of thegearing as hereinafter described. In the example shown the said pitchcircle rollers and the like are so constructed as to serve as thrustbearings and to prevent undesirable axial or endwise displacementbcooperating with side supports or sur aces,

flanges or the like at or near the pitch circle diameterson adjacent andcoacting rollers or the like. For this purpose the roller support 18 andthe roller track .19 are provided with flanges 18a and 19a that fit ingrooves 16a in the roller 16, and the roller 23 engages with sidesurfaces or flan es at 23a on or adjacent to the roller 17 while theroller 24 en-- gages with side surfaces or flanges-at 24aon or adjacentto the roller 22. In this manner the parts are held against axial orendwise thrust or displacement in both directions. This constructionalso ermits of the use of helical gear wheels an pinions without the useof ordinary thrust bearings. In assem- 4 bling the rollers 16 and'thecompound planets 5 and 6 they are placed within the track 19 andinternal teeth 15 in the annulus respectively so as to lieagainst eachother and after placing the roller supports 18 and 24 in the centralposition, the can be rolled around these supports into their properpositions to frnit' of other parts being fitted or assem- The inner endof the driving shaft 2, the annular driven sun wheel 7, the end-cageplate 9 and the annulus late 13, are provided with internally disposeddogs or teeth 2a, 7a, 9a and 13a respectively. 'Splined around'the saiddriven shaft 3 is a slidable sleeve 25 havr ing external dogs 25a whichare adapted to engage at different times with any one of the sets ofdogs 2a, 7a, 9a and 13a by slidable movement of the sleeve in eitherdirection,

for which purpose the sleeve can be' slidably moved in and throughtheannular driven sun wheel7. The said dogs 25a are preferably butnotnecessarily of such length that while they can engagewith the dogs 7awith the dogs 7a for the urpose of loc ing the gearing so that it wirotate bodily as heremafter described. Balkin or sync ro-, nizing meanshereinafter, more ully referred they can 7 when engaging with the-dogs2a also en age to are provided for the pur ose of revent-.

ing the dogs 25a on the slidable s eeve 25 from engaging with the dogs7a on the driven sun wheel 7 or with the dogs' 2a on the driven. shaft2, until such time as the rotating members to be engagedattain'rotational synchronism. On the exterior of the cage plate 8,peripheral dogs or teeth 8a are formed and similar dogs or te'eth 12aareformed on the rear part of the annulus,

locking means being provided for engaging I i with these external dogsor teeth to hold either the cage 10 or the annulus 12 against rotationas hereinafter described. The

sleeve 25 is slidably moved for, the"p1 1rp )se of engaging its dogs 25awith any of the sets of dogs 2a,.7a, 9a or 13a, by means of an" to thecollars 2512 the operating lever 26, the said collars how- 1 tions inthe plane of the longitudinal axis of the gearing or in different planesacross the said axis. The lower part of the lever 26 is formed with afork 28 to which ispiv- S otally attached a slotted plate 29 that isloosely connected with the said sleeve 25 by means of collars 25b insuch manner that the plate 29 can be angularly moved relatively bytransverse movement of ever enabling the sleeve 25 to be slidably movedwhen the operating lever is moved in the longitudinal direction. On thelower part of the said plate 29 is a slotted or bifurcated portion 30that is slidably attached to the upper end of awide, arm or lever 31fixed on a shaft or spindle 32 that is adapted to be rocked in bearingsin the lower part of the casing 1 when the lever 31 is moved bytransverse movement of the operating lever 26. Fixed on the said shaft32, are cam levers 33 and 34 which are angularly disposed as shown inFigure 4. The cam lever 33 engages with a roller 35 which serves toconnect the inner ends of two bell crank levers 36, 36 that are pivotedon pins 37 mounted in fixed bearings in the casing l the outer ends ofthese bell crank levers hav- (1 ing pawls 38 (see Figures 4 and 4a)pivot- 4 ally mounted thereon and co-operating therewith in such mannerthat the pivotal movement is resisted by the springs 39. These pawls 38are adapted to engage with the locking dogs 12a on the annulus 12 atdiametrically opposite points and they are so connected with the bellcrank levers36 that the springs serve as shock absorbers when the pawlsengage with the dogs 12a for which purpose the springs 39 in the exampleshown are associated with plungers 39a that bear against curvedabutments or restraining surfaces formed in the levers 36. Any suitableconstruction of resilient or shock absorbing pawls may be provided. Thebell crank levers 36 are under the influence of springs 40 which tend tomaintain the said levers is necessary that engage with the with africtional surface as shown in Figures 1, 3 and'5. This ring 41 is alsoproin the position in which the pawls 38 are .in engagement withthevided with oppositely. disposed notches 42 adjacent to each of whichare two inclined stops or seatings 43 that can be engaged by inclinedseatings said bell crank levers 36. The'inclination of the said seatingsis preferably about 6. 0 long as each or either projection 44 engageswith one of the inclined stops or seatings 43 the pawls 38 aremaintained'out of engagement with the annulus dogs 120, but upon thesaid balk tionally displaced for example by reason of its frictionalcontact 13, the seatings 43 move away from the proyections' 44 so thatthe latter are free to enter the notches 42 in the plate 41 under theinfluence of the springs 40, which latter there-,

on projections '44 an the ing ring 41 being rotawith the annulus platefore at the same time cause the pawls 38 to engage with the annulus dogs12a. though the balking rin displacedas aforesaid t e contact with theannulus face or plate 13 issufiiciently antifrictional owing to theloose mounting of the ring. to avoid undue heating and wear Al- 41 isfrictionally by rotation of the annulus.

- The other cam lever 34 on the shaft 32 engages with a roller 45 thatconnects two bell crank levers 46'pivote'd at 47 similar to the bellcrank levers 36 and carrying pawls 48 that are adapted to en age withthe locking ogs So on the cage'plate 8 the said pawls 8 co-operatingwith shock absorbing springs 49 in a similar manner to that described inconnection with the pawls "38. Similar balking or synchronizingmeans'are provided for preventing locking pawls 48 with the cage dogs8w, except at the proper time, these means compri ing a balking ring 51-(see Figures 1, 3 and 5) having notches 52 and associatedlm engagementof the clined faces or seatings 53 with which cooperate'projections 54on the bell crank le- Were 46 in a similar manner to that hereinbeforedescribed with reference. to the'balking means associated with thelocking pawls 38 that engage with the annulus dogs 12a. The bell cranklevers 46 are acted upon by springs '50as shown in Figures 5 and 8'to 11and the balking ring 51 is ada ted to be displaced by its contact withthe cage plate 8. The angular disposition of the aforesaid cam levers 33and 34 is such ace of the that angular movementof the shaft 32 caused Iby transversel 26 wil1,accord ing to the direction 0 movement, causeeither one or other of the said cam levers to move and operate themechanism for withdrawing the respective locking pawls from engagementwith the annulus dogs or the cage dogs, whilst subsequent movement inthe same direction will displace the other cam lever and allow itsrespective pawls to be moved under the influence of the springsassociated therewith moving theoperatin lever towards engagement withthe corresponding dogs on the ans-g In order that either of the balkingrings 41 or 51 can be displaced at will to release the locking pawls sothat the latter can engage with t r respective dogs, the cam levers 33and 34 have associated therewith projections 33a and 34a respectivelywhich are adapted to co-operate with lugs 41a and 51a onthe balkingrings when required. The projections 33a and 34a are adapted to engagewith the said lugs 41a and 51a by imparting movement to the operatinglever 26'beyond the normal amount required for gear changin and when theoperating lever is so moved, the said pro'ections en age with the lugsfor displacing t e particu ar balking ring concerned, thus allowing itsassociated awls to engage with the required dogs. or this purpose theoperating lever 26 may be provided with a spring influenced catch 55 onthe end of a sleeve having; late 56 at its upper end adjacent to a 0 orgripping less 57 on the upper end of the operating ever, this knob orgripping piece being pi'votall mounted on the said lever and provid withan arm 58 that can enga e with the said plate 56. The operating ever ismovable in a gate 60 aving a medlal or longitudinal slot 61 and lateralslots 62, 63, 64,

and disposed as shown in Figures13 to 20 one end of the medial slot 61extending beyond the slots 64 and 65 so as to form a notch 66 into whichthe operating lever can be moved and retained as hereinafter described.Lon itudinal movement of the operatin lever in either direction in themedial s 0t imparts sliding movement to the aforesaid sleeve 25 havingthe dogs 25a that can engage with the sets of dogs 2a, 7a, 9a and 13a.Transverse movement of the operatin lever into the lateral slots on oneside of t e medial slot will operate the mechanism that enables thepawls say 38 to engage with the annulus'dogs 12a while transversemovement of the operating lever in the other direction will operate themechanism that enables the locking pawls 48 to engage with the cage dogs8a as hereinafter described.

The said catch 55 on the operating lever forms a stop for engaging withthe ends of the lateral slots so as to limit the movement of theoperating lever when this is actuated for the different forward speeds.By lifting the said plate 56 against the action of its as: sociatedspring while gripping-the knob 57 the catch 55 can be raised so that itno longer acts as a stop, thus permitting the operatmg lever .to bemoved to the extra extent required for causing the projections 33a or3411 ,rto engage with the balking ring lugs 41a or 5 1a so as todisplace either, of the balking rmgs 41 or 51. The said catch 55 alsoe11 gages with projections 60a von the gate 60 or holding the operatinglever 26 in neutral, while itcan also enga e with a catch 66a associatedwith a note 66 when the operating lever is moved to engage top gear ashereinafter more fully-described.

Figure 13 illustrates the gearing and the operating lever 26 in theposition they occupy when the gearing is set for reverse. In order toplace the gearing in this position, the operating lever 26 is moved inthe gate 60 to the end of the slot 61 opposite to the slot 62, thismovement resulting in the sleeve 25 being axially or slidably displacedso that its dogs 25a are brought into engagement with the dogs 13a on te annulus 12. The operating lever 26 is then moved into the slot 62,this movement causing the aforesaid lever 31 to be operated in adirection which displaces the cam lever 34 to allow the spring 50 toactuate or tend to actuate the associated mechanism for causing thelocking pawls 48 to engage with the dogs 8a on the cage plate 8 theother locking pawls 38-pertaining .to the annulus external dogs 12abeing maintained out of .engagement so that the annulus is freetorotate. Figure 13 shows'the dogs 25a and 13a engaged and the pawls 48engaging with the cage dogs 8a, whilst the locking pawls 3811 are shownout of engagement with the annulus external dogs 12a. When the parts arein the positions s shaft 2 imparts rotation to the planet pinions 5through the driving sun wheel 4 fixed on the said shaft 2 and s theplanet pinions are 7 own in this figure, the driving- 5 which mesh withthe internal rection of rotation of the driving shaft and v the sunwheel 4 fixed thereon, so that owing to the dogs 25a on the sleeve 25which is splined on the driven shaft. being in engagement with the dogs13a on the rotating annulus, the driven shaft 3 is rotated to providethe reverse drive. When moving the operating lever 26 into the slot 62for reverse, the balking ring 51 is usually in a position to prevent thelocking pawls 48 from engaging with the external dogs 8a on the cageplate 8. The operating lever can therefore be moved to an extentrequired to enable one of the projections 34a on the cam lever 34 toengage with the appropriate lugs 51a on the balking ring 51 which isthereby displaced to allow the retaining projections 54 to move into theslots 52 (see Figure 11) and thus permit the pawls 48 to engage with theexternal dogs 8a on the cage plate 8 owing to the springs 50 acting onthe bell crank levers 46.

In order to engage first or .emergency low gear, the operating lever26is moved out of I revolve together with th 1 with the dogs 25a. on

the interna'l'dogs 9a on the the slot 62 into the slot 61, whichmovement results in the cam lever 34 actuating the aforesaid mechanismfor withdrawing the pawls 48 out. of engagement with cage while theother pawls 38 remain out of enga ement with the dogs 12a on theannulus12. the slot 61 towards the lateral slot 63 to the poslition shown inFigure 14 (which isa neutra sleeeve 25 being withdrawn from the internaldogs 13d on theannulus. The lever 26 is moved from the neutral positionalong the slot 61 to the slot 63 which resultsin the dogs 25a on theslidable sleeve 25 engaging with cage plate 9 while the latefal movementof the lever 26 into the slot 63 causes the lever'31 and the shaft 32 tobe rocked to displace the cam lever 33, which therefore releases thebell crank levers 36 so that they are moved by the springs 40 to causethe locking pawls 38 to engage with the annulus external dogs 12a andthus lock the annulus against rotation, the other locking pawls 48 beingmaintained-out of engagement with the dogs 811 on the tion of the partswhich is shown the 'drive is transmitted from shaft 2 and the fixed sunwheel 4 to theplanet pinions 5, which, owing to the annulus beingeld'against rotation by the locking pawls 38, e free cage 10 around theaxis of the gearing at a speed less than that of the driving shaft, cagewhich engages by means of its dogs-9a the sleeve 25 splinedtto thedriven shaft, drives the driven shaft at the reduced-speed-whichrepresents first gear or emergency low speed. If the balking plate orrin 41 should be in a position toprein Figure 15 the driving ventthe locing pawls 38 from engaging with the dogs 12a for instance in startingfrom 4 rest, the displacing projections 33a on the cam lever 33 arecaused to 41a on the balking plate movement to theoperatinglever 26 inthe slot 63 after raising the catch 55 thus displace ing the ring andallowing thelocking pawls 38 to be moved into engagement with theannulus dogs 12a by the springs 40.

Movement of the operating lever 26 out of the slot 63 results in thelocking pawls 38 being disengaged from the external dogs 12a on theannulus, and movement of the operating lever along the slot 61 to theneutral position shown in Figure 16 causes the sliding sleeve 25 to beaxially displaced so thatits dogs 25a are withdrawn from engement withthe internal cage dogs 9a.

or the purpose of engaging second or ordinary low gear the operatinglever 26 is moved along the middle slot 61 towards the slot 64 so as toslide the sleeve 25 in the direction for enabling its dogs 25a'to engagewith the internal dogs 7a on the driven sun wheel 7.

the dogs 8a on the Iovement of the operating lever alon position)results in the dogs 25a on the cage. In this posi-- so that therevolving engage with the lug by imparting extra.

Engagement'of the said dogs 25a and 7a is however prevented by means ofa balking or synchronizing ring 67 (see Figures 1 and 21 to 24) untilwheel 7 and the driven shaft 3 with the sleeve 25 are rotating at the.same speed. The balking rin in the enlarged fragmentary section view inFigure 21 is provided with a coned surface that bears against a matingsurface on washer 68 made of an anti-frictional material .fixed 67 asshown more clearly such time as the driven sun withinthe said driven sunWhelTand it is also provided with internal projections 69 that canassume a position in the path of the dogs 25a on the slidable sleeve 25to obstruct the latter and prevent-them from engaging with the dogs 7 aon the port ring 70 having internal projections 71 that fit in splines72 on the sleeve 25, is connected with the said balking ring'67 so as tobe capable of rotating the latter, by means of a projection 73 on thebalking ring en'- gaging with a slot 74 in the support ring of such sizethat a limited rotational displacement of the balking ring can takeplace rela-' 7 by reasonof the frictional contact with the washer 68,and its projections 69 are therefore held in the POSltlOIl'ShOWII in thedeveloped plan View in Figure 22 to *prevent engagement of the dogs 25awiththe dogs 7a on the sun wheel 7 By decelerating the engine andreducing the speed of the driving sha-ft2, the rotational s eed of thesun wheel 7 will be decreased an when it tends to be less than that ofthe driven shaft 3, a frictional drag is exerted on the balking ring 67by means of the washer 68, thus displacing the said balking ring 67relatively to the support ring 70 owing to the lost motion between theprojection 73 and the elongated slot 74, with the result that thebalking ring projections69 are moved out of the path of the dogs 25a,which can therefore be slid into engagement with the dogs 7a on the sunwheel as shown in Figures 23 and 24 the said projections 69 passingbetween the dogs 25a and fitting in splines 75 in the slidable sleeve 25so that the balking ring 67 is maintained in a definite position inwhich it is held against relative or unrequired rotationaldisplacemen't'during other operations of the gearing. The operatinglever 26 can now be moved into the slot 64, (see Figure 17) to free orrelease the mechanism that/tends" to engage the lockingpawls 48 with.the exsun wheel-7. A supn ternal dogs 8a on the cage. At the time thatthe sun wheel7 attains. the same speed been moved into the slot 64,

i Q or medium low speed) bein imparted to the as that of the drivenmember 3,'the planet cage 10 which had been rotatin in a forwarddirection for first gear is decelerating and by the time that theoperatin lever26 has" the ca e 10 has commenced to rotate in the reverseirection. This reverse rotation of the cage 10 maintains thesynchronizer or balking plate or ring 51, which is in frictional contactwith the cage plate 8 in a position in which its inclined seatings 53are engaged b the seatings on the projections 54 o the 11 crank levers46 to prevent the locking pawls 48 from engaging with the external dogs8a on the cage as shown in Figures 8 and 10. Upon accelerating theengine in the ordinal-g way, the cage w l decelerate again and at t emoment it stops and tends to reverse its direction of rotation, it willfrictionally displace the synchronizer or balking plate or ring 51 so asto caum the seatings 53 thereon to be moved out of engagement withthebalking rejections 54 (see Figure 11) with the resu t that the pawls 47are caused to engage with the external do s So on the cage (see Figure9) under the nfluence of the springs v 50 at or about the moment thatthe cage is stationary. The parts are now in the sition mitted from thedriving shaft 2 and the drivmg sun wheel 4 to the planet pinions 5 and6, which, owing to the planet 0 e 10 being held against rotation by theloliing pawls 48, revolve on their own axes the annulus being free atthis time so that the smaller planet pinions 6 which are in mesh withthe driven sun wheel 7 drive the latter at a speed less than that of.the driving shaft, this reduced speed (which represents second geardriven shaft 3 throu h t e engaging sun wheel dogs 7 a and the 0 a onthe slidable sleeve 25 which is spline .to the driven shaft. By movingthe operating lever 26 out of the with the sun wheel dogs 7a because theslide.-

ble sleeve 25 has not been axially moved, the ,gearm merely rotates idlyin this position.

- In c angmg from second gear to third gear, the operatin' lever 26 ismoved out of v a the slot 64 across t e slot 61 and into the slot 65.The first art of this movement results in the mechanlsm being operatedfor with:

. drawing the locking awls 48 from engage ment with the cage ogs 8a asaforesaid in connection with Figure 18 while the latter part of themovement, i. e, fromthe position shown in Figure 18 intothe slot 64 asshown in Figure 19 frees or releases the mechanismshown in Figure 17,and the drive is transslot 64 into the slot 61, as shown in Figure 18,

the lockinghpawls 38 and permitting them to o s 12a on the anengage witthe external nu us under the influence o the springs or at about themoment the annulus is stationary. The slidable sleeve 25 is not axiallydisplaced inchanging from the second gear to third gear, so'

that the dogs 25a,on this sleeve remain in engagement with the internaldogs 70 on the sun wheel 7. The various parts areinow inthe' positionillustrated in gure 19 and the drive is transmitted from the drivingshaft-2through the sun wheel 4 so as to rotate the planet cage 10 andthe planet pinions about the axis of the gearing, the planet pinionsrevolving about their own axes owing to the larger pinions. 5 revolvinginm'esh with the internal teeth 15 of the annulus 12 which is now lockedby the pawls 38 so that the sun wheel 7 is driven by the smaller lanetpinions 6 at a speed less than that of t 0 driving shaft 2 thisspeedwhich is higher than that imparted when the parts are in the positionshown in Fi re 17 and which represents third gear or igh speed beingimpartedto the driven shaft 3 through the enga ing sun .wheel dogs 7aand the dogs 25a on t e sleeve shaft. g

When it is desired tochange from third gear to second gear the operatinlever 26 1S merely moved out of the slot 65 into the slot 64 and theengine accelerated in the usual way.

n changing from thlrd gear to top gear the operating-lever 26 is'movedout of the slot 65 and into the slot 66. v The initial or lateralmovement of the lever 26 into the medial slot 61 asshown in Figure18causes the mechanism to be operated for movingthe locking pawls 38 outof engagement with the external dogs 12a on the annulus 12' and thefurther movement of the said lever towards and into the slotor notch 66,which is an extension ofthe medial slot 61, tends to move the slidablesleeve 25 so that its dogs 25a will enga with the dogs 2a on the drivingshaft 2. e engagement of the dogs 25a and 2a is however revented whilethe driving shaft 2 and the riven shaft 3 are rotating at differentspeeds by means of abalking or synchronizin ring 76 (see Figures 1 and25 to 28) whicfi is rovided with projections 77 25 splined on the driventhat tends to engage the locking pawls 88.

having 6 inclined faces or seatings that are with the external dogs 12aonthe annulus 12.

adapted to be engaged by similar inclined

